The standoff between airport security and a sitting US senator police briefly detained Kentucky senator Rand Paul after he refused the security pat down at Nashville's airport. Also -- a presidential candidate Ron Paul -- an outspoken critic of spring practices ABC's Jim -- has the story. Kentucky senator Rand Paul's trip to Washington in erupted by the TSA. One of the 3% of American flyers stopped for a personal pat down. The -- at Nashville's airport targeted his leg as suspicious and he missed his flight after refusing to allow any TSA agent to pat him down. Instead asking to go through the scanner a second time. I offered to show my leg in fact they've shown my leg repeatedly and how should I go back through this -- And they said now. The senator's staff -- -- he's currently being detained by TSA. I was told not to leave. A few vocal and and I did step outside -- people thought was sort of surrounded and that bat in the cubicle. Senator -- father run the Texas libertarian running for president who wants to TSA shut down. Called the incident evidence the police state in this country is growing out of control. The TSA tells ABC news senator Paul was treated as everyone else's. Once anyone starts the screening process and the machine alerts screeners to something suspicious. They must submit to targeted pat downs or lead. Security experts say the TSA touch is safer for the second -- Ordinarily a pat down of your knee is not a particularly sensitive thing and touching the name means that you can't hide whatever is there. The senator Paul is not backing down this morning he wrote in the letter to The Washington Times. He will introduce legislation requiring the TSA to allow passengers to be re screened rather than patted down if they set off an alarm.

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